There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{(1149.75 - 9.198x)}{(1 + e^{6.9634 - 0.0522t})} - 7.1t - 500\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = - \frac{9.198x}{(e^{-0.0522t + 6.9634} + 1)} + \frac{1149.75}{(e^{-0.0522t + 6.9634} + 1)} - 7.1t - 500\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( - \frac{9.198x}{(e^{-0.0522t + 6.9634} + 1)} + \frac{1149.75}{(e^{-0.0522t + 6.9634} + 1)} - 7.1t - 500\right)}{dx}\\=& - 9.198(\frac{-(e^{-0.0522t + 6.9634}(0 + 0) + 0)}{(e^{-0.0522t + 6.9634} + 1)^{2}})x - \frac{9.198}{(e^{-0.0522t + 6.9634} + 1)} + 1149.75(\frac{-(e^{-0.0522t + 6.9634}(0 + 0) + 0)}{(e^{-0.0522t + 6.9634} + 1)^{2}}) + 0 + 0\\=& - \frac{9.198}{(e^{-0.0522t + 6.9634} + 1)}\\ \end{split}\end{equation} \]

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